3D Printed Stealthy Dual Laser ‘Trip Wire’ Enhances The Security Where Ever You Need It

Thanks to the ever-expanding DIY culture, projects that might formerly have seemed somewhat formidable to less-experienced makers are almost fait accompli. Now, basically, if there’s a will, there’s an Instructable providing the way. For instance, if you’re concerned about the security of your home, you can now make your own exterior home security system and you can do it pretty cheaply using the step-by-step instructions provided for this recent Instructables project–a 3D Printed Stealthy Dual Laser Perimeter Security Receiver.

This system can be used outside of your residence to create a secure perimeter. As the maker says:

“This is a dual laser based perimeter defense system that can be used outside of your residence to create a perimeter to notify you if someone is too close to your home and to make a noise to let the intruder know that you are now aware of their presence. (Disclaimer, this is not a life saving device and is to be considered as a toy.)”

It is only a receiving unit as it is designed to be used with any laser pointing devices mounted according to your preferences.

A new Instructables project, posted recently by a maker who goes by the screen name of “RomeoThecla,” the project does require some basic experience with electronics. The .stl files are free to download so that you can print them yourself. If you don’t have a 3D printer, you can use one of the many web-based services like Shapeways or a 3D printing community like 3D Hubs that lets you find a printer in your area.

This system is different than the single-laser tripwire systems as the circuits have been modified so that small animals, leaves, or the like won’t set off the alarm. To the more basic, single-laser system, the designer added a secondary photocell and a potentiometer, which means that you can set the dual-laser system alarm to sound if only one or both lasers trigger; this is an added measure to prevent false alarms. This unit, which utilizes a thermometer for which you’ll be 3D printing a case (also to contain other components), “works well,” says its maker, “when you mount two separate lasers and aim them toward this receiving unit’s photocells.” However, if you prefer to mount the lasers in a different lawn ornament–there’s the stealth feature!–you can then point the lasers at the receiver.

If you want to make this system yourself, it’s pretty cheap to do so. To make the system, you’ll print these 12 parts, for which the .stl files are provided:

• Mounting bolts (2)
• Photo sensor mounts (2)
• Resized threaded round nuts (2)
• Box bottom
• Box top
• Cap spacers (2)
• Top mount
• Bottom mount

In addition to the 3D printing (or just the filament if you have your own 3D printer), it should cost you around $25 or $30 to make it, which is pretty great compared to expensive security systems and live monitoring. There’s a list of parts and materials you’ll need on the Instructables page. You can get most of them from Radio Shack (numbers are included) or eBay. The base outdoor thermometer, for example, is only about a $3 part, if you use the one recommended from the Home Depot. For those who find visuals helpful, the Instructables page also photographs of parts and schematics, and even a video of the wiring of the circuit board so you’ll have plenty of help navigating the making process.

Once you make it through the wiring, just assemble the components together and you’re ready to set your system up in the yard.

“Test [your] lasers,” the maker says, suggesting you just “sit back and let your family test it out for you, by surprising them with the alarm when they walk through it.”

There’s another version of this system coming soon according to its maker, so stay tuned for an update. If you do take this project on, be sure to share adjustments and refinements and, better still, successes with the Instructables community as well as “RomeoThecla.” Let us know how this project works out for you in the 3D Printed Dual Laser Perimeter Security forum thread over at 3DPB.com.